We cruised with Carnival on the Victory after sailing with Royal Caribbean 5 times in a row, so I had some expectations going in that did not get satisfied however, overall you get out of anything what you put into it so, we had a great time.
Embarkation: Please, somebody tell somebody at Carnival to separate out those that have prepared to travel with those who have not... if you have all of your paperwork filled out, go to this line; not prepared, go to that line. This may train people to be more prepared.
Ship and crew: Difficult to get around without a map (and there aren't any), the shopping seemed boring and uninspired same ol' same ol', the photographers couldn't seem to focus their cameras, the casino was great but some of the staff was pushy and rude, typical overtly aggressive drink vendors, and the ship was clean but not sparkling clean. The decor and color pallet is dark, I think the decor is better suited to the Mexican Riviera than the Caribbean. The staff was friendly if you engaged them however, overall they didn't go out of their way to engage you in pleasant conversation or even say hello in the hallways as you passed... strangely distant. Fellow passengers: This was a pleasant surprise for me... I found a great mix of people from all walks of life, all ages, and not too many of one group or another, and except for the one cranky group of old folks in Jamaica that don't comprehend "Island Time" all were friendly and wonderful to be with for a week.